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This is Scientific American's 60-Second Science. I'm Cynthia Graber. This will just take a minute.

Real-time information about what’s happening in our bodies at the cellular¹ level could be crucial for fighting cancer and other life-threatening conditions. It would be incredibly helpful to know whether cancer drugs are reaching their targets or whether toxins² are disrupting DNA³ in healthy cells. Now scientists at M.I.T. have created carbon nanosensors that they say can help answer those questions. The research was published December 14th in the journal Nature Nanotechnology.

The researchers wrapped carbon nanotube sensors⁵ in DNA, and the coated sensors have been shown to be safe for living cells. The nanotubes emit infrared⁶ light. But that signal changes when cancer drugs or molecules⁸ that damage DNA bind⁹ with the sensor⁴.

By detecting the changes in signals, such as intensity¹⁰ and wavelength¹¹, the researchers have shown they can determine just what’s happening to cells in real-time. So if the sensor were placed in the body, it could pick up, for example, even a molecule⁷ of hydrogen peroxide, which is toxic¹² to DNA. Researchers say these nanotube-DNA sensors could monitor cellular activity over long periods of time. They might also be used in minimally¹³ invasive biopsy techniques, because cells would be transmitting information directly to the radiologist.

Thanks for the minute for Scientific American's 60-Second Science. I'm Cynthia Graber.

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1 cellular
adj.移动的；细胞的，由细胞组成的
参考例句：
She has a cellular telephone in her car.她的汽车里有一部无线通讯电话机。 Many people use cellular materials as sensitive elements in hygrometers.很多人用蜂窝状的材料作为测量温度的传感元件。

2 toxins
n.毒素( toxin的名词复数 )
参考例句：
The seas have been used as a receptacle for a range of industrial toxins. 海洋成了各种有毒工业废料的大容器。 Most toxins are naturally excreted from the body. 大部分毒素被自然排出体外。来自《简明英汉词典》

3 DNA
(缩)deoxyribonucleic acid 脱氧核糖核酸
参考例句：
DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。 Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。

4 sensor
n.传感器，探测设备，感觉器（官）
参考例句：
The temperature sensor is enclosed in a protective well.温度传感器密封在保护套管中。 He plugged the sensor into a outlet.他把传感器插进电源插座。

5 sensors
n.传感器，灵敏元件( sensor的名词复数 )
参考例句：
There were more than 2000 sensors here. 这里装有两千多个灵敏元件。来自《简明英汉词典》 Significant changes have been noted where sensors were exposed to trichloride. 当传感器暴露在三氯化物中时，有很大变化。来自辞典例句

6 infrared
adj./n.红外线(的)
参考例句：
Infrared is widely used in industry and medical science.红外线广泛应用于工业和医学科学。 Infrared radiation has wavelengths longer than those of visible light.红外辐射的波长比可见光的波长长。

7 molecule
n.分子，克分子
参考例句：
A molecule of water is made up of two atoms of hygrogen and one atom of oxygen.一个水分子是由P妈̬f婘̬ 妈̬成的。 This gives us the structural formula of the molecule.这种方式给出了分子的结构式。

8 molecules
分子( molecule的名词复数 )
参考例句：
The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。 Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里，大分子裂变为小分子。

9 bind
vt.捆，包扎；装订；约束；使凝固；vi.变硬
参考例句：
I will let the waiter bind up the parcel for you.我让服务生帮你把包裹包起来。 He wants a shirt that does not bind him.他要一件不使他觉得过紧的衬衫。

10 intensity
n.强烈，剧烈；强度；烈度
参考例句：
I didn't realize the intensity of people's feelings on this issue.我没有意识到这一问题能引起群情激奋。 The strike is growing in intensity.罢工日益加剧。

11 wavelength
n.波长
参考例句：
The authorities were unable to jam this wavelength.当局无法干扰这一波长。 Radio One has broadcast on this wavelength for years.广播1台已经用这个波长广播多年了。

12 toxic
adj.有毒的，因中毒引起的
参考例句：
The factory had accidentally released a quantity of toxic waste into the sea.这家工厂意外泄漏大量有毒废物到海中。 There is a risk that toxic chemicals might be blasted into the atmosphere.爆炸后有毒化学物质可能会进入大气层。

13 minimally
最低限度地，最低程度地
参考例句：
Food spoilage problems occur with minimally processed, concentrated frozen citrus products. 食品的变质也发生在轻微加工的、浓缩冷冻的柑橘制品中。 So, minimally, they are responsible for such actions and omissions. 所以，至少来说，他们要对这样的行为和忽略负责。